Universal refill mechanism and method

Abstract

A mechanism for automatically adjusting the chamber length in a writing instrument to accommodate refills of different lengths. The mechanism comprises at least first and second elements operably engaged with each other. When contacted by a refill, the second element automatically moves from a first position associated with a first chamber length to a second position associated with a second chamber length. A biasing member may releasably hold the second element in the first position. In one embodiment third element is fitted within the second element, and is operably and movably engaged with the first and second elements. When contacted by a refill, the third element automatically moves from a first position associated with a first chamber length to a second position associated with a second chamber length. A method of using an automatically-adjusting refill seat mechanism is also disclosed.

What is claimed is:  
     
       1. An automatically-adjusting refill seat mechanism for a writing instrument, said mechanism comprising: 
       a first element having a first seating surface configured and adapted to engage a first seating end of a first type of refill having a first length, said first element configured and sized to fit in a writing instrument having an internal chamber for containing refills, said first element having a longitudinal axis;  
       a second element having a second seating surface configured and adapted to engage a seating end of a second type of refill having a second length, said second element axially movable with respect to said first element from a first position to a second position, said second element configured and adapted to allow the first seating end of the first type of refill to be inserted therethrough for contacting said first seating surface;  
       wherein:  
       inserting the first type of refill in the writing instrument engages said first seating surface defining a first refill chamber length; and  
       inserting the second type of refill in the writing instrument engages at least said second seating surface and automatically moves said second element from said first position to said second position defining a second refill chamber length.  
     
     
       2. The refill seat mechanism of  claim 1 , wherein said first element is a rod and said second element is a hollow sleeve movable over at least a portion of said first element. 
     
     
       3. The refill seat mechanism of  claim 1 , further comprising a biasing member interposed between at least part of said first element and at least part of said second element to bias said second element into said first position of said second seating surface. 
     
     
       4. The refill seat mechanism of  claim 1 , wherein said second chamber length is greater than said first chamber length. 
     
     
       5. The refill seat mechanism of  claim 1 , wherein: 
       said first element has a head;  
       said refill seat mechanism further comprises a rod operably engaged with said head;  
       said head is axially movable with respect to said rod from a first position to a second position; and  
       when said head is engaged by a seating end of a third type of refill having a third length and configured to engage said second element, said head automatically moves from said first position to said second position defining a third chamber length.  
     
     
       6. The refill seat mechanism of  claim 5 , further comprising a biasing member interposed between at least part of said second element and at least part of said rod to bias said second element into said first position of said second element. 
     
     
       7. The refill seat mechanism of  claim 5 , wherein: 
       said rod is elongated and has first and second ends and an axial opening extending at least partially into one of said ends;  
       a stem projects from said head; and  
       said stem is slidably engaged in said axial opening.  
     
     
       8. The refill seat mechanism of  claim 7 , wherein: 
       said rod has angular surfaces facing said head and said head has mating angular surfaces facing said rod angular surfaces;  
       said angular surfaces of said rod and head are unmeshed when said head is in said first position of said head; and  
       said angular surfaces of said rod and head are meshed when said head is in said second position of said head.  
     
     
       9. An automatically-adjusting refill seat mechanism for a writing instrument, said refill seat mechanism comprising: 
       a rod configured and adapted to fit in a writing instrument, said rod having an outside surface, a first end with angled surfaces, and a second end;  
       a hollow sleeve configured and adapted to fit in and to slide within the writing instrument, said sleeve slidably engaging at least a portion of said rod and having an inside surface;  
       a biasing member interposed between at least a portion of said rod and at least a portion of said sleeve; and  
       a seat movably disposed inside said sleeve and having a head and a stem, said head having angled surfaces cooperatively configured and adapted to engage said angled surfaces of said rod;  
       wherein said seat is automatically movable from a first position in which said angled surfaces of said rod and said seat are prevented from meshing, thereby defining a first chamber length for a first refill in said writing instrument, to a second position in which said angled surfaces of said rod and said seat mesh, thereby defining a second chamber length for a second refill in the writing instrument.  
     
     
       10. The refill seat mechanism of  claim 9 , wherein said rod has raised ears extending radially outwardly from said outside surface and said sleeve has splines extending radially inward from said inside surface, said splines defining channels for slidably engaging said ears. 
     
     
       11. The refill seat mechanism of  claim 10 , wherein said rod has raised rails extending radially outwardly from said outside surface and longitudinally aligned with said raised ears. 
     
     
       12. The refill seat mechanism of  claim 11 , wherein said seat has raised tabs extending radially outwardly and sized to be slidably engaged in said channels. 
     
     
       13. The refill seat mechanism of  claim 12 , wherein at least part of said raised tabs have angled sides and said splines have angled ends. 
     
     
       14. The refill seat mechanism of  claim 9 , wherein said rod has an opening therein configured and adapted to receive at least part of said stem of said seat. 
     
     
       15. The refill seat mechanism of  claim 9 , wherein said biasing member is a helical spring. 
     
     
       16. The refill seat mechanism of  claim 9 , wherein: 
       said head has a seating surface configured for abutment with an end of a refill such that the refill can effect automatic adjustment of said refill mechanism upon contacting and pushing said seating surface; and  
       the refill is movable out of abutment with said seating surface to permit another refill to abut said seating surface.  
     
     
       17. A writing instrument having a variable length refill chamber comprising: 
       a housing defining an elongated internal chamber having a length to hold a refill cartridge, said housing having a lower portion and an upper portion coupled together;  
       an automatically-adjusting refill seat mechanism disposed in said housing, said refill seat mechanism comprising:  
       a first element having a first seating surface configured and adapted to engage a first seating end of a first type of refill having a first length, said first element configured and sized to fit in a writing instrument having an internal chamber for containing refills, said first element having a longitudinal axis;  
       a second element having a second seating surface configured and adapted to engage a seating end of a second type of refill having a second length, said second element axially movable with respect to said first element from a first position to a second position, said second element configured and adapted to allow the first seating end of the first type of refill to be inserted therethrough for contacting said first seating surface;  
       wherein:  
       inserting the first type of refill in the writing instrument engages said first seating surface defining a first refill chamber length; and  
       inserting the second type of refill in the writing instrument engages at least said second seating surface and automatically moves said second element from said first position to said second position defining a second refill chamber length.  
     
     
       18. The writing instrument of  claim 17 , further comprising a biasing member is interposed between at least a portion of said first element and at least a portion of said second element. 
     
     
       19. A writing instrument comprising: 
       a housing having upper and lower portions defining an elongated chamber therein for containing a refill cartridge having one of at least two different lengths, a writing end, and an opposite seating end, said elongated chamber having a length;  
       a first seating element configured and adapted for selectively engaging the seating end of a refill cartridge upon insertion of the refill cartridge in said housing; and  
       a second seating element configured and adapted for selectively engaging the seating end of a refill cartridge upon insertion of said refill cartridge in said housing, said first and second seating elements slidably with engaging each other, both said seating elements being disposed elongated chamber of said housing;  
       wherein said first and second seating elements are movable with upon engagement by a refill cartridge upon insertion of the refill cartridge in said housing to adjust the length of said housing chamber automatically to correspond to one of the refill cartridge lengths such that the refill is held in a proper position for writing.  
     
     
       20. The writing instrument of  claim 19 , wherein said upper portion of said housing is closed, thereby enclosing said first and second seating elements such that movement of said first and second seating elements is effected solely from within said elongated chamber in the housing. 
     
     
       21. A method for using refills of different lengths in a refillable writing instrument, said method comprising: 
       providing a writing instrument having a housing defining an elongated internal chamber, the housing and chamber each having a length, the housing having a lower portion and an upper portion coupled together;  
       providing an automatically-adjusting refill seat mechanism in the chamber, the mechanism comprising:  
       a first seating element configured and adapted for selectively engaging the seating end of a refill cartridge upon insertion of the refill cartridge in the housing;  
       a second seating element configured and adapted for selectively engaging the seating end of a refill cartridge upon insertion of the refill cartridge in the housing said the first and second seating elements being slidably engaged with each other;  
       uncoupling the lower and upper portions of the housing;  
       inserting a refill having a length into the chamber; and  
       recoupling the lower portion and the upper portions of the housing;  
       whereupon the refill engages at least one of the first and second seating elements and the first and second seating elements are movable with respect to each other to automatically adjust the chamber length to hold the refill in a proper position for writing without requiring manual adjustment of the housing or chamber lengths or the relative positions of the seating elements.  
     
     
       22. The method of  claim 21 , wherein the seating elements are enclosed in a closed end of the housing such that movement of either seating element is effected solely from within the chamber in the housing by said inserting of a refill into the chamber. 
     
     
       23. A writing instrument for containing refills of different lengths, said writing instrument comprising: 
       a housing having an internal chamber therein for containing a refill having a writing end and an opposite seating end;  
       a first seating element having a first surface for selectively contacting the seating end of a first type of refill; and  
       a second seating element having a second surface for selectively contacting the seating end of a second type of refill, said second seating element operably engaged with the first seating element and automatically axially movable with respect thereto upon contact by the refill, the first and second seating elements being disposed in the internal chamber of the housing;  
       wherein the movability of said second seating element with respect to said first seating element enables refills of different lengths to be used and properly positioned in said writing instrument for writing automatically without manual adjustment of said internal chamber.  
     
     
       24. The writing instrument of  claim 23 , wherein: 
       said housing has an open distal writing end through which the writing end of a refill end is extendable and a closed proximal non-writing end closing off said internal chamber;  
       said first and second seating elements are positioned within said closed end of said housing; and  
       said second seating element is moved by contact by the refill within said internal chamber.  
     
     
       25. An automatically-adjusting refill seat mechanism for a writing instrument, said refill seat mechanism comprising: 
       a rod configured and adapted to fit in a writing instrument, said rod having chamber positioning and sleeve-receiving portions;  
       a sleeve configured and adapted to fit in the writing instrument for slidable movement therein, said sleeve slidably engaging at least a portion of said sleeve-receiving portion of said rod and slidable upon contact with a refill of a given length and configuration;  
       a seat disposed in said sleeve and engageable with said sleeve-receiving portion of said rod, said seat moveable from a first position to a second position;  
       wherein said rod, sleeve, and seat are arranged and configured such that contact with a refill automatically adjusts the position of said seat with respect to said rod.  
     
     
       26. A writing instrument automatically adaptable to accommodating refills of different lengths, said writing instrument comprising: 
       a housing having an internal chamber for containing a writing instrument refill having a writing end and an opposite seating end, said housing having a length, an open writing end at one end of the length through which a writing end of a refill extends, and a closed end at the other end of the length closing said internal chamber from access from outside said housing;  
       a first seating surface disposed in said housing along said length of said housing, said first seating surface configured and adapted to engage a seating end of a first type of refill having a first length, said first seating surface being located at a first position along said length of said housing when the first type of refill is inserted in said housing, said first position being associated with a first chamber length; and  
       a second seating surface disposed in said housing along said length of said housing, said second seating surface configured and adapted to engage a seating end of a second type of refill having a second length which is different from the first length, said second seating surface being located at a second position along said length of said housing which is different from said first position when the second type of refill is inserted in said housing, said second position being associated with a second chamber length which is different from said first chamber length;  
       wherein said writing instrument automatically provides a proper seating surface position and chamber length for a writing end of either the first or second type of refill to extend out the writing end of the housing upon insertion of the refill in said housing without manual adjustment of said first or second seating surfaces.  
     
     
       27. The writing instrument of  claim 26 , wherein said first seating surface is annular in shape and raised above said second seating surface. 
     
     
       28. The writing instrument of  claim 23 , wherein said first and second seating surfaces are configured such that the first seating end of the first type of refill may engage said first seating surface without engaging said second seating surface. 
     
     
       29. The writing instrument of  claim 26 , wherein seating surface and said second seating surface form a cup-shaped refill seat of unitary structure. 
     
     
       30. The writing instrument of  claim 26 , wherein said first and second seating surfaces are not accessible from outside said internal chamber for manual adjustment.